A stand-up bag made of a heat-sealable plastic film, in particular for fluent substances, that is liquids or granules, typically has a front panel and a back panel that are joined at their longitudinal edges by welds and an inwardly folded lower end panel and an also inwardly folded upper end panel. The front panel and the upper end panel are joined by a transverse weld. A closure is provided at a joint between the front panel and the upper end panel and is connected in a fluid-tight manner to the adjacent faces of the upper end panel and the front panel. The closure may be designed as a pour spout that is closed for example by a cap. The plastic film may be a multilayer coextruded film or composite film that has a heat-sealable polymer layer forming the inner face of the bag.
Such a stand-up bag is particularly suited for packaging of liquid and viscous products. However, packaging of pourable granular solids is also possible. The possible applications range from the packaging of beverages, liquid concentrates, liquid cleaners, and liquid fertilizers, to viscous personal care products, as well as cereals and rice.
Stand-up bags having the above-described features are known from DE 31 19 179 A1 and U.S. Pat. No. 6,796,712. Compared to blow-molded packaging containers, they are characterized by much lower weight and also have the advantage that the empty containers may be transported in a space-saving manner and, after being emptied, may be refolded and disposed of in a space-saving manner. However, due to their low degree of dimensional stability flexible bags are more difficult to handle when pouring out the contents. It is difficult to hold the bag when the contents is being poured out, since the bag panels are flexible and the shape as well as the volume of the bag constantly change during emptying of the contents. Metered emptying of contents requires some skill. The problems become greater with increasing container size.